alleryIf 3:5 = x:20, what is x?
A8
B10
C15
D12
Answer & Solution
Correct answer: D. 12
1. A proportion says the two ratios are equal.
2. 5 became 20, so multiply by 4; apply the same to 3.
3. x = 3 x 4 = 12.
_Source: Wikipedia, Ratio, Notation and terminology_
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